Worm farming, producing worm castings, potting soil Repurposing of natures product, using coffee grounds and brewing grains help feed and nourish the soil. The earthworms like it so do the plants! Earthworm excrement is highly enriched with minerals that assist in plant growth! Harold Houser is making a difference in his own way! including earthworm farming, the creation of healthy food growing mediums and chemical-free gardening.